Aromatic compounds and their use in perfumery

ABSTRACT

The compounds of formula ##STR1## wherein symbol X represents a --CHO group or an acetal group of formula ##STR2## symbols R&#39;, taken separately, represent each a C 1  to C 4 , linear or branched, saturated or unsaturated, hydrocarbon radical or, taken together, represent a C 1  to C 4  alkylene radical, which may be substituted, and symbol R represents a hydrogen atom or a methyl radical, are useful as perfuming ingredients for the preparation of perfuming compositions and perfumed articles, to which they impart floral type notes.

TECHNICAL FIELD

The present invention relates to novel aromatic acetals and aldehydeswhich are useful as perfuming ingredients. It concerns, in fact,compounds of formula ##STR3## wherein symbol X represents a group --CHOor an acetal group of formula ##STR4## symbols R', taken separately,represent each a C₁ to C₄, linear or branched, saturated or unsaturated,alkyl radical or, taken together, represent a C₁ to C₄ alkylene radical,which may be substituted, and symbol R represents a hydrogen atom or amethyl radical.

PRIOR ART

As is apparent from the following table, several compounds having astructure close to that of compounds (I) are known from the prior art,some of which have met with commercial success. Furthermore, several ofthese compounds are described in the textbook of S. Arctander, Perfumeand Flavor Chemicals, Montclair, N.J., USA (1969), as is indicated inthe table.

                                      TABLE                                       __________________________________________________________________________    Compounds          Odor       Reference                                       __________________________________________________________________________     ##STR5##          very strong, floral lily of the valley                                                   Naarden Int.- product sheet                      ##STR6##          floral, green, lime-blossom                                                              Arctander 496                                    ##STR7##          floral, green, cucumber, melon, lime-blossom                                             Arctander 758                                    ##STR8##          floral, sweet, green, fruity                                                             Arctander 2741                                   ##STR9##          floral, sweet, spicy                                                                     Arctander 2073                                   ##STR10##         floral, green, lily of the valley                                                        NL 7905175                                      __________________________________________________________________________

In spite of the abundance of known products of this type, the researchactivity in this field remains intense, namely with the aim of findingcompounds which present a greater variety of odor nuances and alsocompounds whose stability in composition is improved over that of theknown products. In fact, these known aldehydes are very sensitive tooxidation, being easily converted to their corresponding acids, whichare either odorless or have unpleasant fragrances, but, in any case, donot possess any longer the desired odor characters.

DESCRIPTION OF THE INVENTION

We have now surprisingly discovered that compounds (I) possess veryuseful odor properties, which are also distinct from those of the priorart products. In particular, we have observed that3-(4-tert-butyl-2-methyl-1-phenyl)propanal according to the invention iscapable of replacing advantageously, in its typical applications,p-tert-butyl-α-methyl-hydrocinnamic aldehyde or3-(4-tert-butyl-1-phenyl)-2-methyl-propanal, also known under thetradename of LILIAL® (origin: Givaudan-Roure, Vernier, Switzerland),while being, in practice, of a wider use than the latter.

This result of our researches was totally unexpected since, despite thelarge number of novel compounds prepared by us and possessing alkyl oralkenyl groups in the different positions of the benzene ring and of theside chain, only compounds (I), and in particular the derivative whereinR=H, have shown exceptional odor characters. The latter became in factevident as a result of laborious olfactive evaluations carried out bypanels of expert perfumers, who surprisingly discovered the superiorodor quality of these compounds, which was apparent not only upon theevaluation on smelling strip of the compound in a pure state or incomposition, but also upon its use for perfuming namely detergents andfabric softeners.

Thus, it has been ascertained that3-(4-tert-butyl-2-methyl-1-phenyl)propanal, the preferred compound ofthe invention, develops an odor which is reminiscent of that of theknown aldehyde cited above, but which in addition possesses a perfectlydistinct anisic, lily of the valley character.

Furthermore, as is apparent from the examples presented further on, thiscompound according to the invention, relative to the above-cited knownaldehyde, possesses an enhanced odor strength and better stabilityagainst oxidation. Thus, the invention provides a compound which is morestable than known LILIAL® and which is as convenient for use in thecompositions wherein the latter is typically employed, as for thepreparation of original compositions.

The compounds of the invention can be advantageously used both in fineand technical perfumery and, as a result of their odor properties, areof much wider application than prior knownp-tert-butyl-α-methyl-hydrocinnamic aldehyde. They are convenient forpreparing perfuming bases and perfumes and are also very useful forperfuming a variety of consumer products such as soaps, bath or showergels, shampoos and after-shampoo products, cosmetic preparations and airor body deodorants. On the other hand, thanks to the strength andsubstantivity of its odor note, 3-(4-tert-butyl-2-methyl-1-phenyl)propanal in particular has revealed itself exceptionally advantageousfor perfuming detergents or fabric softeners. The household products canalso be perfumed by means of compounds (I).

In such applications, they can be employed in a wide range ofconcentrations. By way of example, concentrations of the order of 5 to10%, or even 15 or 20% by weight, relative to the weight of thecomposition into which they are incorporated, can be cited.

It is quite clear, however, that such values can only be cited in anindicative capacity, since the concentrations of compound (I) aredependent both on the olfactive effect one desires to achieve and on thenature of the product to be perfumed. On the other hand, they alsodepend on the nature of the other ingredients present in a givencomposition, whenever compounds (I) are used in admixture with currentsolvents, adjuvants and perfuming co-ingredients. Specific descriptionof such co-ingredients is not warranted here. The prior art is rich inexamples thereof and the skilled person is able to select those mostappropriate for the odor effect sought-after. One can cite as areference example the textbook of S. Arctander, Perfume and FlavorChemicals, Montclair, N.J., USA (1969).

Concentrations well below those above-cited, of the order of 0.1 to 0.5%by weight, relative to the weight of the composition into which they areincorporated, will normally be used when compounds (I) are applied forperfuming the varied consumer articles above-cited, for example soaps,detergents and fabric softeners.

Compounds (I) are prepared according to an original process which isalso the object of the invention and which is characterized in that analcohol of formula ##STR11## wherein symbol R represents a hydrogen atomor a methyl radical, is reacted with an oxidizing agent known to becapable of oxidizing the alcohol function into aldehyde, in an inertorganic solvent, to obtain an aldehyde of formula (I), and, whereapplicable, the latter aldehyde is converted into the correspondingacetal in a generally known manner.

As an oxidizing agent, there can be used any reagent of current use inreactions of alcohol oxidation into aldehyde, of which many examples canbe found in reference works such as for example the textbook of H.O.House, Modern Synthetic Reactions, W.A. Benjamin Inc. 2^(nd) ed., USA(1972).

The reaction will be carried out in an inert organic solvent of currentuse in this type of reactions. Examples of such solvents can be found inthe reference work cited above.

The compounds of formula (II) are aromatic alcohols which can beprepared from commercial products, according to the following reactionscheme: ##STR12##

Furthermore, another synthesis of3-(4-tert-butyl-2-methyl-1-phenyl)-1-propanol (R=H) has been describedby P. Cagniant et al. in Bull. Soc. Chim. France, 1969, 985.

If desired, the aldehydes of formula (I) can be converted into thecorresponding acetals via methods which are well-known to the skilledperson. Such methods include for example reacting the aldehyde (I) withan appropriate alcohol or diol, in the presence of an acid catalyst[see, for example, J. March, Advanced Organic Chemistry, Reactions,Mechanisms & Structure, section 6--6, 3^(rd) ed., John Wiley & Sons, USA(1985)].

Alternatively, the compounds of formula (I) can be prepared by anotheroriginal process, characterized in that an aldehyde of formula ##STR13##wherein R has the meaning indicated in formula (I), is subjected tocatalytic hydrogenation, in an inert organic solvent and, if necessary,the aldehyde (I) thus obtained is then acetalyzed in a generally knownmanner.

The hydrogenation reaction takes place in the presence of a catalystsuch as Pd-C, under the conditions described further on.

The starting products of formula (IV) are novel compounds, prepared fromo-xylene, according to the following reaction scheme: ##STR14##

The first step in this process is a conventional alkylation, carried outin the presence of catalytic amounts of AlCl₃ [see P. Cagniant et al.,ref. cited]. The 4-tert-butyl-1,2-dimethylbenzene thus obtained is thenelectrochemically oxidized into the corresponding acetal. The latter isthen converted into the aldehyde (IV) which is not methylated in thechain, by way of a condensation reaction of the Muller-Cunradi type[see, for example, U. von der Bruggen et al., J. Org. Chem..53, 2920(1988) and references therein], using a Lewis acid such as, for example,ZnCl₂, but carried out in the presence of phosphoric acid.

The conditions under which the reactions represented in schemes I and IIwere carried out are described in greater detail in the followingpreparation examples, wherein the temperatures are indicated in degreescentigrade and the abbreviations have the usual meaning in the art.

The invention will also be described in further detail by way of theperfumery application examples presented further on.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 shows the graph related to the experiment described in Example18.

EMBODIMENTS OF THE INVENTION EXAMPLE 1

Preparation of 3-(4-tert-buty1-2-methyl-1-phenyl)propanal

a) Method according to scheme I

To a suspension of pyridinium chlorochromate (PCC, 13.4 g, 62.0 mmole)in CH₂ Cl₂ (80 ml) there was added at room temperature a solution of3-(4-tert-butyl-2-methyl-1- phenyl)-1-propanol (9.1 g, 44 mmole) in CH₂Cl₂ (20 ml). After 15 h, the mixture was diluted with ether (200 ml),filtered and passed through a column of Florisil® (chromatographyadsorbant; origin: Fluka, Switzerland). The eluting agent wasconcentrated and distilled to provide the desired propanal with 90%purity (yield 54%).

M.p. 81°-83°, recrystallized (-30°/petroleum ether)

IR(neat): 2960, 2900, 2860, 2810, 2720, 1725, 1610, 1510, 1460, 1390,1270, 1140, 1110, 1040, 885, 830 cm⁻¹

NMR(¹ H, 360MHz, CDCl₃): 9.83(broad, 1H); 7.18(s, 1H); 7.16(d, J=9Hz,1H); 7.06(d, J=9Hz, 1H); 2.95-2.87(m, 2H); 2.76-2.68(m, 2H); 2.31(s,3H); 1.30(s, 9H) δppm

NMR(¹³ C, 90.5MHz, CDCl₃): 201.8(d); 149.3(s); 135.4(s); 135.4(s);128.2(d); 127.4(d); 123.1(d); 44.0(t); 34.3(s); 31.4(3q); 25.0(t);19.6(q) δppm

MS: 204(18), 189(100), 171(10), 161(9), 145(75), 133(15), 131(19),130(20), 119(15), 115(18), 105(23), 91 (18), 87(3), 77(8), 65(6),57(14), 41 (13)

Odor: described above.

The starting 3-(4-tert-butyl-2-methyl-1-phenyl)-1-propanol was preparedaccording to scheme I, from 3-(4-tert-butyl-1-phenyl)propanal (origin:Quest Int.). We proceeded as follows. Under N₂ and at room temperature,0.5 moles of 3-(4-tert-butyl-1-phenyl)propanal in diethylether wereadded slowly to a suspension of LiAlH₄ (0.5 mol eq.) in ether. Thereaction was followed by thin layer chromatography and was completedwithin 15 minutes after the end of the introduction. The reactionmixture was cooled to 0° and treated with a 1 N solution of NaOH(solution volume=5 times the weight of LiAlH₄ used in the reaction). Theether phase was filtered and the solvant evaporated to obtain3-(4-tert-butyl-l-phenyl)-1-propanol (yield 83%, purity 88% ).

IR(neat): 3320, 2940, 2850, 1500, 1450, 1405, 1385, 1365, 1260, 1050,1010, 825 cm⁻¹

NMR(¹ H, 360MHz, CDCl₃): 7.31 (d,=9Hz, 2H); 7.14(d, J=9Hz, 2H);3.72-3.63(m, 2H); 2.71-2.64(m, 2H); 1.94-1.84(m, 2H); 1.56-1.50(broad,1H); 1.32(s, 9H) δppm

NMR(¹³ C, 90.5MHz, CDCl₃): 148.7(s); 138.8(s); 128.1(2d); 125.3(2d);62.3(t); 34.3(s); 34.2(t); 31.5(t); 31.4(3q) δppm

MS: 192(15), 177(100), 159(13), 147(4), 131(53), 117(24), 105(12),91(28), 77(6), 57(12),41(14)

The above-mentioned propanol was then converted into1-tert-butyl-4-(3-methoxymethoxypropyl)benzene by means ofdimethoxymethane, in an analogous manner to that described by J. L. Graset al. in Synthesis 74, (1985), but using 12 equivalents ofdimethoxymethane for 1 equivalent of alcohol. The above-mentionedmethoxymethylether was then transformed as described by A. Rieche etal., Chem. Ber. 95, 91 (1962) but using dichloromethane as solvent. Theconcentration of methoxymethylether in this solvent varied between 0.1and 0.3 M. The reaction product was purified by chromatography toprovide 8-tert-butyl-1,3,4,5-tetrahydro-2-benzoxepine (yield 67%,purety>99%).

B.p. 92°/16 Pa

M.p. 49°

IR(neat): 2940, 2880, 2820, 1500, 1445, 1430, 1355, 1250, 1220, 1100,1095, 1030, 995, 970, 910, 895, 880, 830, 815, 750, 730, 670 cm⁻¹

NMR(¹ H, 360MHz, CDCl₃): 7.22-7.13(m, 2H); 7.10(d, J=7.2Hz, 1H); 4.66(s,2H); 4.07-4.02(m, 2H); 2.99-2.93(m, 2H); 1.87-1.80(m, 2H); 1.30(s, 9H)δppm

NMR(¹³ C, 90.5MHz, CDCl₃): 149.0(s); 139.6(2s); 128.9(d); 125.7(d);124.5(d); 75.7(t); 75.6(t); 35.0(t); 34.3(s); 31.4(3q); 30.5(t) δppm

MS:204(17), 189(100), 171(15), 147(24), 145(55), 131(21), 115(22),105(24), 91 (28), 77(12), 71 (9), 65(10), 57(25), 51 (4), 41 (20)

Odor: floral, white flowers, dusty, chemical.

The above-mentioned tetrahydrobenzoxepine was dissolved in ethyl acetate(solution 1.5 M) and stirred at room temperature with 5% Pd/C (1%weight/weight relative to the benzoxepine) under hydrogen. Once thereaction was complete (a few hours), the catalyst was filtered and thesolvent evaporated under reduced pressure to provide the desired3-(4-tert-butyl-2-methyl-1-phenyl)-1-propanol 88% pure (yield 83%).

B.p. 110°/13 Pa

IR(neat): 3300, 2940, 2850, 1500, 1460, 1350, 1270, 1050, 1030, 820, 810cm⁻¹

NMR(¹ H, 360MHz, CDCl₃): 7.18-7.11(m, 2H); 7.07(d, J=9Hz, 1H); 3.7(t,J=7.2Hz, 2H); 2.68-2.64(m, 2H); 2.32(s, 3H); 1.89-1.79(m, 2H);1.6(broad, 1H); 1.31 (s, 9H) δppm

NMR(¹³ C, 90.5MHz, CDCl₃): 148.8(s); 138.9(s); 135.4(s); 128.5(d);127.2(d); 122.8(d); 62.6(t); 34.2(s); 33.0(t); 31.4(3q); 29.0(t);19.6(t) δppm

MS:206(23), 191(65), 173(15), 161(5), 145(100), 131(90), 119(18),117(17), 115(20), 106(24), 105(47), 91 (30), 77(15), 72(4), 65(8),57(42), 44(12), 41 (35)

Odor: floral.

b) Method according to scheme II

To 360 g (1.78 mole) of 3-(4-tert-butyl-2-methyl-1-phenyl)-2-propenal inethanol (1 kg) there was added 5% Pd-C (3 g) and potassium acetate (360g, 2 mmole). The mixture was hydrogenated at 40° and at a pressure of4×10⁵ Pa during 24 h. After filtering the catalyst and evaporating thesolvent, distillation under vacuum (Vigreux column, 22 cm) provided thedesired 3-(4-tert-butyl-2-methyl-1-phenyl)propanal (310 g, 93% pure,yield 85%). The analysis of this compound gave the same results as thosecited under a).

The starting unsaturated aldehyde was prepared according to scheme II,as follows.

To o-xylene (Fluka purum, 905 ml, 7.5 mole), kept under stirring, at 0°,there was added AlCl₃ (6.7 g, 50 mmole), and then, dropwise, tert-butylchloride (Fluka puriss., 551 ml, 5 mole), during 1.25 h, while keepingthe temperature between 0° and 5° (the evolving HCl was trapped in NaOH2.5 N). The temperature was allowed to increase to room temperature.After 60 h, the reaction mixture was poured on a mixture of ice andether, the organic phase was successively washed with brine (2x), H₂ O,sat. NaHCO₃ and brine, dried over Na₂ SO₄ and distilled under vacuum(Vigreux column, 30 cm) to provide 4-tert-butyl-1,2-dimethylbenzene(purity >99%, yield 90%).

B.p. 92°-95°/17×10² Pa

IR(neat): 3030, 2980, 2890, 1520, 1470, 1455, 1370, 1280, 1150, 825 cm⁻¹

NMR(¹ H, 360MHz, CDCl₃): 7.16(broad s, 1H); 7.13(broad d, J=8, 1H);7.06(d, J=8, 1H); 2.27(s, 3H); 2.23(s, 3H); 1.30(s, 9H) δppm

NMR(¹³ C, 90.5MHz, CDCl₃): 148.7(s); 136.0(s); 133.5(s); 129.4(d);126.7(d); 122.7(d); 34.2(s); 31.5(3q); 20.0(q); 19.1(q) δppm

MS: 162(M⁺, 28), 147(100), 131(6), 119(43), 107(22), 91(17), 77(7),65(4), 41(6)

The 4-tert-butyl-1,2-dimethylbenzene (430 g, 265 moles) waselectrochemically oxidized at a temperature of about 35°, in an inoxreactor, in methanol solution (2l, 1580 g), using sodiump-toluenesulfonate as electrolyte and a cell of the EBERSON/WITMER type,with carbon electrodes, passing a current of 29 mA/cm², during 18.5 h.There were obtained 564.5 g of4-tert-butyl-1-(dimethoxymethyl)-2-methylbenzene, 75% pure. This rawproduct was purified by distillation (b. p. 119°-126°/13 hPa) to providea colorless liquid 77% pure (yield 66%) which was used as such in thefollowing step.

IR(neat):2950, 2890, 1600, 1445, 1350, 1220, 1185, 1110, 1090, 1050,970, 820 cm⁻¹

NMR(¹ H, 360MHz, CDCl₃): 7.44 (d, J=8, 1H); 7.21(dd, J₁ =8, J₂ =2, 1H);7.16(d, J=2, 1H); 5.42(s, 1H); 3.32(s, 6H); 2.36(s, 3H); 1.30(s, 9H)δppm

NMR(¹³ C, 90.5MHz, CDCl₃): 151.2(s); 135.6(s); 132.8(s); 127.6(d);126.3(d);

122.3(d); 102.1(d); 53.1(2q); 34.4(s); 31.3(3q); 19.1(q) δppm

MS: 222(M⁺, 2), 191(100), 176(16), 161(14), 133(10), 115(7), 105(13),91(9), 75(8), 65(3), 41 (5)

Odor: green, wax, slightly cuminic, petroleum.

To the above-mentioned acetal (708 g, 2.6 mole) was rapidly added, at-10° and under stirring, a solution of ZnCl₂ (14.2 g, 104 mmole), inethyl acetate (136 ml). After 5 min, H₃ PO₄ at 85% (1.23 ml, 182 mmole)was added and the solution, which had turned yellow, cooled down to-20°. After 15 rain, ethylvinylether (Fluka purum, 377 ml, 3.9 mole) wasadded dropwise during 1.5 h, while maintaining the temperature between0° and 5°. At the end of the addition, the color of the reaction mixturehad become violet. After 1 h at 0° and 15 h at room temperature, thechromatographic analysis indicated the formation of 73% of theintermediate acetals. This raw mixture of acetals was added by means ofa cannula to a mixture of formic acid (650 ml), sodium formate (213 g)and water (338 ml), and the whole was heated for 3 h with a bath at 110°, while continuously distilling the volatiles (b. p. 90°/106 Pa). After1 h at 110° and 15 h at room temperature, the solidified mixture wasdiluted in water (250 ml) and petroleum ether 30°- 50° for extraction.The organic phase was washed, dried and concentrated. The raw product(667 g, 68% pure, yield 86%) was crystallized several times in petroleumether 30°-50°, at 0°, to provide 3-(4-tert-butyl-2-methyl-1-phenyl)-2-propenal having a purity above 99% (yield 78%).

M.p. 75°-77°

IR(CHCl₃): 2950, 1665, 1595, 1140, 1095, 965 cm⁻¹

NMR(¹ H, 360MHz, CDCl₃): 9.70(d, J=8, 1H); 7.75 (d, J=16, 1H); 7.54(d,J=8, 1H); 7.28(d broad, J=8, 1H); 7.25(s broad, 1H); 6.65(dd, J₁ =16, J₂=8, 1H); 2.48(s, 3H); 1.32(s, 9H) δppm

NMR(¹³ C, 90.5MHz, CDCl₃): 193.9(d); 154.7(s); 150.2(d); 137.7(s);130.1(s); 128.8(d); 128.1(d); 126.8(d); 123.7(d); 34.8(s); 31.1(3q);20.0(q) δppm

MS: 202(M⁺, 10), 87(100), 159(9), 145(92), 128(15), 115(22), 105(4),91(10), 77(5), 55(8), 41 (8)

Odor: aldehydic, metallic.

EXAMPLE 2

Preparation of 3-(4-tert-butyl-2-methyl-1-phenyl)-2-methylpropanal

A method identical to that described in example 1 a) was followed, butusing as starting product3-(4-tert-butyl-2-methyl-1-phenyl)-2-methyl-1-propanol.3-(4-tert-Butyl-2-methyl-1-phenyl)-2-methylpropanal was obtained with apurity above 99% (yield 68%).

B.p. 100°-110°/9 Pa

IR(neat): 3400, 2940, 2820, 2800, 2690, 1710, 1600, 1450 cm⁻¹

NMR(¹ H, 360MHz, CDCl₃): 9.71 (d, J=2.9Hz, 1H); 7.17(s, 1H); 7.16(d,J=7.9Hz) 7.04(d, J=7.9Hz, 1H); 3.06(dd, J₁ =14.4Hz, J₂ =7.2Hz, 1H);2.71-2.59(m, 1H); 2.53(dd, J₁ =14.4Hz, J₂ =9Hz, 1H); 2.31(s, 3H);1.30(s, 9H); 1.11(d, J=6.7Hz) δppm

NMR(¹³ C, 90.5MHz, CDCl₃): 149.3(s); 204.2(d); 135.5(s); 134.0(s);129.4(d); 127.4(d); 122.9(d); 46.8(d); 34.2(s); 33.5(t); 31.4(3q);19.7(q); 13.5(q) δppm MS:218(18), 203(57), 185(8), 173(3), 161(100),145(27), 133(23), 131(24), 119(13), 105(16), 91(16), 77(8), 57(15), 41(13)

Odor: floral, green, aromatic, fenchylic.

The starting 3-(4-tert-butyl-2-methyl-1-phenyl)-2-methyl-1-propanol wasprepared in a manner identical to that described in example 1 a) for itshomologue non-methylated in the chain, but starting from3-(4-tert-butyl-1-phenyl)-2-methylpropanal (origin: Givaudan-Roure). Theanalytical data for the intermediate products were the following:

3-(4-tert-butyl-1-phenyl)-2-methyl-1,-propanol (purity: 99%)

Yield 99%

IR(neat): 3340, 2960, 2870, 1460, 1360, 1270, 1040, 850 cm⁻¹

NMR(¹ H, 360MHz, CDCl₃): 7.30(d, J=8Hz, 2H); 7.10(d, J=8Hz, 2H);3.53(dd, J₁ =11Hz, J₂ =6Hz, 1H); 3.46(dd, J₁ =11Hz, J₂ =6Hz, 1H);2.71(dd, J₁ =14Hz, J₂ =6Hz, 1H); 2.40(dd, J₁ =14Hz, J₂ =8Hz, 1H);1.93(m, 1H); 1.44(s, 1H); 1.31 (s, 9H); 0.92(d, J=7Hz, 3H) δppm

NMR(¹³ C, 90.5MHz, CDCl₃): 148.8(s); 137.6(s); 128.8(2d); 125.2(2d);67.8(t); 39.3(t); 37.8(t); 34.4(s); 31.4(3q); 16.6(q) δppm

MS: 206(16), 191(100), 173(11), 159(3), 147(30), 131(28), 117(25),105(15), 91(30), 77(8), 65(5), 57(22), 41 (14)

1-tert-butyl-4-(2-methyl-3-methoxymethoxypropyl)benzene (purity:>99%)

Yield 87%

IR(neat): 2940, 2910, 1450, 1355, 1260, 1145, 1105, 1040, 915 cm⁻¹

NMR(¹ H, 360MHz, CDCl₃): 7.29(d, J=7.9Hz, 2H); 7.09(d, J=7.0Hz, 2H);4.63(s, 2H); 3.44-3.33(m, 2H); 3.37(m, 3H); 2.76(dd, J₁ =14.4Hz, J₂=7.2Hz, 1H); 2.37(dd, J₁ =14.4Hz, J₂ =7.2Hz, 1H); 2.09-1.96(m, 1H);1.31(s, 9H); 0.92(d, J=6.7H, 3H) δppm

NMR(¹³ C, 90.5MHz, CDCl₃): 148.6(s); 137.6(s); 128.9(d); 128.8(d);125.1(2d); 96.7(t); 72.8(t); 55.2(q); 39.5(t); 35.5(d); 34.4(s);31.5(3q); 17.0(q) δppm MS: 250(3), 218(19), 203(65), 188(5), 173(34),147(100), 145(23), 132(25), 131(84), 117(32), 105(17), 91 (30), 77(6),57(73), 45(58)

8-tert-butyl-1,3,4,5-tetrahydro-4-methyl-2-benzoxepine (purity:>99%)

Yield 76%

M.p. 50°-51° C.

IR(neat): 3030, 2940, 2860, 1495, 1350, 1113, 1090 cm⁻¹

NMR(¹ H, 360MHz, CDCl₃): 7.20(dd, Jhd 1=7.94Hz, J₂ =1.8Hz, 1H); 7.09(d,J=7.94Hz, 1H); 4.69(s, 2H); 4.07(dd, J₁ =10.8Hz, J₂ =6Hz, 1H); 3.59(dd,J₁ =10.8Hz, J₂ =3.6Hz); 2.87-2.81(m, 2H); 2.0-1.9(m, 1H); 1.31(s, 9H);0.89(d, J=6.71Hz, 3H) δppm

NMR(¹³ C, 90.5MHz, CDCl₃): 149.1(s); 139.4(s); 137.8(s); 129.5(d);125.5(d); 124.5(d); 81.5(t); 75.5(t); 42.7(t); 34.3(s); 34.2(s);31.4(3q); 17.8(q) δppm

MS: 218(29), 203(100), 185(12), 173(24), 161(54), 145(41), 133(22),131(25), 115(23), 105(21 ), 91 (32), 77(12), 65(10), 57(32), 41 (20)

3-(4-tert-buty1-2-methyl-l-phenyl)-2-methyl-1-propanol (purity: 99%)

Yield 99%

B.p. 130°-140° C./3-7 Pa

IR(neat): 3600, 3500, 2920, 1590, 1440, 1020 cm^(-`)

NMR(¹ H, 360MHz, CDCl₃): 7.15(s, 1H); 7.14(d, J=9Hz, 2H); 7.04(d, J=9Hz,2H); 3.57(dd, J₁ =11Hz, J₂ =6.1Hz, 1H); 2.71(dd, Jhd 1=14.0Hz, J₂=6.7Hz, 1H); 2.38(dd, J₁ =14.0Hz, J₂ =9Hz, 1H); 2.31(s, 3H);1.98-1.87(m, 1H); 145(s, 9H); 0.95(d, J=6.7Hz, 3H) δppm

NMR(¹³ C, 90.5MHz, CDCl₃): 148.9(s); 135.9(s); 135.6(s); 129.6(d);127.3(d); 122.6(d); 68.1(t); 36.7(s); 36.7(t); 34.2(s); 31.4(3q);19.8(q); 16.8(q) δppm

MS:220(25), 205(91), 187(8), 173(4), 161(100), 145(33), 131(35),119(22), 115(15), 105(28), 77(9), 57(25), 41(17)

EXAMPLE 3

Preparation of 4-tert-butyl-1-(3,3-dimethoxypropyl)-2-methylbenzene

To a solution of 3-(4-tert-butyl-2-methyl-1-phenyl)propanal (1.06 g, 5mmole) in methanol (10 ml), at room temperature, there was added conc.HCl (3 drops). After 3 h, the solution was poured into a mixture ofether and sat. NaHCO₃ for extraction. The organic phase was washed withNaHCO₃, dried over K₂ CO₃ and concentrated. After bulb-to-bulbdistillation, the desired product was obtained with 89% purity andpresenting the following analytical characters:

IR(neat): 2960, 2870, 1605, 1500, 1460, 1385, 1360, 1270, 1195, 1130,1085, 1060, 990, 960, 920, 885, 830 cm⁻¹

NMR(¹ H, 360MHz, CDCl₃): 7.21(m, 2H); 7.13(d, J=8, 1H); 4.48(t, J=6,1H); 3.40(s, 6H); 2.68(m, 2H); 2.37(s, 3H); 1.93(m, 2H); 1.35(s, 9H)δppm

NMR(¹³ C, 90.5MHz, CDCl₃): 148.8(s); 136.7(s); 135.4(s); 128.4(d);127.2(d); 122.8(d); 104.0(d); 52.6(2q); 34.2(s); 32.8(t); 31.4(3q);27.7(t); 19.6(q) δppm

MS: 250(M⁺, 2), 235(2), 218(20), 203(41), 171(53), 161(78), 131(100),102(24), 75(87), 57(16), 41(9)

Odor: floral, lily of the valley, aldehydic.

EXAMPLE 4

Preparation of 2-[2-(4-tert-butyl-2-methyl-1-phenyl)ethyl]-1,3-dioxolane

A mixture of 3-(4-tert-butyl-2-methyl-1-phenyl)propanal (2.11 g, 9.8mmole), ethyleneglycol (6.1 g, 98 mmole) and p-toluenesulfonic acid (95g, 0.5 mmole) in cyclohexane (25 ml), was heated to reflux (80°) during3 h with a trap of the Dean-Stark type. The cooled mixture was pouredinto ether and aq. sat. NaHCO₃, and the organic phase was washed withaq. sat. NaHCO₂, dried over K₂ CO₃ and concentrated. After bulb-to-bulbdistillation, the desired dioxolane was obtained with a purity of 94%and presenting the following analytical characters:

IR(neat): 2950, 2860, 1600, 1500, 1450, 1400, 1385, 1350, 1140, 1125,1050, 1030 cm⁻¹

NMR(¹ H, 360MHz, CDCl₃): 7.15(m, 2H); 7.09(d, J=8, 1H); 4.92(t, J=5,1H); 4.00(m, 2H); 3.88(m, 2H); 2.70(m, 2H); 2.32(s, 3H); 1.94(m, 2H);1.31(s, 9H) δppm

NMR(¹³ C, 90.5MHz, CDCl₁₃): 148.8(s); 136.7(s); 135.4(s); 128.3(d);127.2(d); 122.8(d); 104.1(d); 64.9(2t); 34.2(s+t); 31.4(3t); 27.0(t);19.5(q) δppm

MS: 248(M⁺, 9), 223(10), 186(19), 171(28), 161(9), 145(20), 131(24),115(15), 106(39), 100(100), 91(15), 87(19), 73(92), 57(30), 45(34),41(13), 29(17)

Odor: floral.

EXAMPLE 5

Preparation of a perfuming composition

A base perfuming composition intended for a feminine type perfume wasprepared by admixing the following ingredients:

    ______________________________________                                        Ingredients          Parts by weight                                          ______________________________________                                        Benzyl acetate       15                                                       Geranyl acetate      8                                                        Lynalyl acetate      35                                                       Styrallyl acetate    4                                                        10%* Cinnamic alcohol                                                                              6                                                        10%* Anisic aldehyde 5                                                        Cyclosia.sup. ®  Base.sup.1)                                                                   7                                                        10%* Damascenone     15                                                       10% β-Dorinone.sup. ®2) in ethyl citrate                                                  12                                                       Ethyl linalol        20                                                       Eugenol              25                                                       Exaltolide.sup. ®3)                                                                            17                                                       Galaxolide.sup. ®4) 50                                                                         55                                                       Hedione ®.sup.5) 60                                                       Heliotropine         44                                                       10%* Hexylix.sup. ®6)                                                                          20                                                       10% Indol in triethylamine                                                                         32                                                       Iso E Super.sup.7)   100                                                      Levocitrol           24                                                       Linalol              20                                                       Phenethylol          5                                                        Polysantol.sup. ®8) a 10%*                                                                     60                                                       Polywood.sup. 9) Super                                                                             15                                                       Benzyl salicylate    110                                                      Pipol salicylate     30                                                       10%* Tagetes essential oil                                                                         12                                                       α-Terpineol    45                                                       10%* Vanilline       8                                                        α-Ionone       14                                                       β-Ionone        52                                                       Dianthine.sup. ®10) SA                                                                         5                                                        Total                880                                                      ______________________________________                                         *in dipropyleneglycol (DIPG)                                                  .sup.1) hydroxycitronellal based mixture; origin: Firmenich SA, Geneva,       Switzerland                                                                   .sup.2) 1(2,6,6-trimethyl-l-cyclohexen-l-yl)-2-buten-l-one; origin:           Firmenich SA, Geneva, Switzerland                                             .sup.3) pentadecanolide; origin: Firmenich SA, Geneva, Switzerland            .sup.4)                                                                       1,3,4,6,7,8hexahydro-4,6,6,7,8,8-hexamethyl-cyclopenta-2-benzopyragne;        origin: International Flavors & Fragrances Inc., USA                          .sup.5) methyl dihydrojasmonate; origin: Firmenich SA, Geneva, Switzerlan     .sup.6) allyl (cyclohexyloxy) acetate; origin: Charabot, France               .sup.7) 1(octahydro-2,3,8,8-tetramethyl-2-naphthalenyl)-1-ethanone;           origin: International Flavors & Fragrances Inc., USA                          .sup.8) 3,3dimethyl-5-(2,2,3-trimethyl-3-cyclopenten-l-yl)-4-penten-2-ol;     origin: Firmenich SA, Geneva, Switzerland                                     .sup.9) perhydro5,5,8atrimethyl-2trans-naphthalenyl acetate; origin:          Firmenich SA, Geneva, Switzerland                                             .sup.10) origin: Firmenich SA, Geneva, Switzerland                       

To this base composition of the floral, green type, there were added, onthe one hand 120 parts by weight of3-(4-tert-butyl-2-methyl-1-phenyl)propanal according to the invention toprepare a novel composition A and, on the other hand, 120 parts byweight of 3-(4-tert-butyl-1-phenyl)-2-methylpropanal to prepare acomposition B.

The two compositions were then evaluated on a blind test by a panel of13 expert perfumers. According to the unanimous opinion of the latter,the novel composition A was preferred for its far sweeter and naturalfloral note than that of composition B. The perfumers also judged thatthe odor of the A composition was stronger and more voluminous than thatof composition B, its odor note appearing far more powdery and thejasmine and lily of the valley characters being clearly exalted.

EXAMPLE 6

Preparation of a perfuming composition

A base perfuming composition intended for a powder detergent wasprepared by admixing the following ingredients:

    ______________________________________                                        Ingredients              Parts by weight                                      ______________________________________                                        Carbinol acetate         15                                                   Lynalyl acetate          30                                                   (3 and 4)-(4-methyl-3-penten-l-yl)-3-cyclohexene-                                                      20                                                   3-carbaldehyde                                                                Amylcinnamic aldehyde    125                                                  50%* Undecylenic aldehyde                                                                              15                                                   50%* Methyl nonyl aldehyde                                                                             15                                                   Citronellol              15                                                   Dihydromyrcenol.sup. ®1)                                                                           15                                                   10%* Exaltolide.sup. ®2)                                                                           30                                                   Geraniol brut            30                                                   Heliotropine             15                                                   Iralia.sup. ®3)      90                                                   Linalol                  25                                                   Lorysia.sup. ®4)     110                                                  Methyl methylanthranilate                                                                              5                                                    Patchouli essential oil  30                                                   Phenylhexanol            25                                                   Polysantol.sup. ®5)  20                                                   Polywood.sup. ®6) Super                                                                            10                                                   Spiranol.sup.7)          10                                                   Terpineol                50                                                   Tonalid.sup. ®8)     70                                                   Phenylacetaldehyde dimethylacetal                                                                      10                                                   Vertofix coeur.sup.9)    40                                                   Dorinia SA.sup.10)       20                                                   Galbex.sup. ®11) 183 10                                                   Total                    850                                                  ______________________________________                                         *in DIPG                                                                      .sup.1) 2,6dimethyl-7-octen-2-ol; origin International Flavors &              Fragrances Inc., USA                                                          .sup.2) see example 3                                                         .sup.3) methylionone (isomer mixture); origin: Firmenich SA, Geneva,          Switzerland                                                                   .sup.4) 4(1,1-dimethylethyl)-l-cyclohexyl acetate; origin: Firmenich SA,      Geneva, Switzerland                                                           .sup.5) see example 3                                                         .sup.6) see example 3                                                         .sup.7) 2,6,10,10tetramethyl-l-oxaspiro[4.5]decan6-ol; origin: Firmenich      SA, Geneva, Switzerland                                                       .sup.8) (5,6,7,8tetrahydro-3,5,5,6,8,8-hexamethyl-2-naphthyl)-l-ethanone;     origin: PFW, Holland                                                          .sup.9) origin: International Flavors & Fragrances Inc., USA                  .sup. 10) origin: Firmenich SA, Geneva, Switzerland                           .sup.11) origin: Firmenich SA, Geneva, Switzerland                       

To this base composition of the floral type there were added 150 partsby weight of 3-(4-tert-butyl-2-methyl-1-phenyl)propanal to prepare anovel composition A, 100 parts by weight of the same compound to preparea novel composition B and 150 parts by weight of3-(4-tert-butyl-1-phenyl)-2-methylpropanal to prepare a composition C.

These three compositions were then used in identical concentrations toprepare three samples, respectively A, B and C, of a perfumed powderdetergent.

A panel of 7 perfumers, evaluating these three detergent samples on ablind test, showed a clear preference for samples A and B, the odor ofwhich was judged more floral-powdery, stronger and more elegant thanthat of sample C.

Three standard batches of textiles were then washed separately in threewashing machines with the samples A, B and C and the odor of thetextiles was evaluated on a blind test by a panel of six expertperfumers. The evaluation was carried out with the wet textiles, justout of the machine, as well as after 24 h of drying in air.

The perfumers unanimously preferred the odor of the textiles treatedwith sample A, both humid and after drying, followed by those treatedwith sample B. The odor of these two batches was judged distinctlysuperior, both in strength and quality, to that of the textiles washedwith sample C, in spite of the fact that the concentration of thecompound according to the invention in sample B was inferior to that of3-(4-tert-butyl-1-phenyl)-2-methylpropanal in sample C.

The odor of the wet linen washed with samples A and B was judged muchmore floral than that of the textiles treated with sample C, whereas thedry textiles developed a much stronger odor, with a powdery-lily of thevalley note, also slightly reminiscent of mimosa, which could not befound in the textiles perfumed with sample C.

EXAMPLES 7-16

The articles mentioned hereinafter were perfumed by adding3-(4-tert-butyl-2-methyl-1-phenyl) propanal to the appropriatenon-perfumed bases, in the concentrations indicated:

    __________________________________________________________________________                    Conc.    Odor/Aspect                                                                          Odor/Aspect                                   Article         (% by weight)                                                                          [25° C.]                                                                      [40° C.]                               __________________________________________________________________________    7 Cologne       5.0      S/N    S/N                                             (alcohol 95°)                                                        8 Cream oil/water                                                                             0.4      S/N    S/N                                           9 Cream water/oil                                                                             0.4      S/N    S/N                                           10                                                                              Shampoo       0.5      S/N    A/N                                           11                                                                              Deodorant (spray)                                                                           1.3      S/N    S/N                                           12                                                                              Spray laque   0.2      S/N    S/N                                           13                                                                              Soap (tallow + coconut oil)                                                                 0.5      S/N    S/N                                           14                                                                              Talc          0.5      S/N    S/N                                           15                                                                              Powder detergent                                                                            0.2      S/N    S/N                                           16                                                                              Antiperspirant roll-on                                                                      0.5      S/N    S/N                                           __________________________________________________________________________     Key to abbreviations                                                          S = stable                                                                    N = normal                                                                    A = acceptable                                                           

The perfuming and stability tests cited in this table showed that3-(4-tert-butyl-2-methyl-1-phenyl) propanal is very convenient forperfuming a variety of consumer products and as a result can find wideuse in perfumery. It was observed that it efficiently covered the odorof the base, where appropriate, and that it imparted to these products avery pleasant and elegant floral, lily of the valley, powdery and mimosaodor.

EXAMPLE 17

Test of stability on smelling strip

Tests of stability on smelling strip were carried out by comparing theperformance 3-(4-tert-butyl-2-methyl-1-phenyl)propanal according to theinvention (smelling strip A) with that of the two known analogues, i.e.3-(4-tert-butyl-1-phenyl) propanal (smelling strip B) and3-(4-tert-butyl-1-phenyl)-2-methylpropanal or LILIAL® (smelling stripC).

Thus, a panel of 4 expert perfumers dipped the smelling strips intovials containing the above-mentioned compounds in a pure form, so as toobtain a soaked zone of about 1 cm in each case. These smelling stripswere then evaluated on a blind test and their odors compared over time,this operation having been repeated every day, until the perfumers couldno longer detect any odor from any of the smelling strips.

According to their opinion, at the begining of the test smelling strip Adeveloped a floral odor wherein the lily of the valley and mimosa typeconnotation was distinctly dominant. In addition, it developed a sweet,anisic and powdery note.

Smelling strip B had a floral, much greener and aldehydic odor, alsomore aggressive than that of smelling strip A, and smelling strip C hada floral odor of the same type as that of smelling strip A, but lessanisic and devoid of the mimosa character.

The evolution in time of the odor intensity of the three smellingstrips, as evaluated by the perfumers on a value scale of 0 to 10, isindicated in the following table (average of the 4):

    ______________________________________                                        S. strip                                                                              3 days  7 d      12 d 15 d   30 d 44 d                                ______________________________________                                        A       5       5        4    3      3    3                                   B       8       4        1    --     --   --                                  C       --      --       --   --     --   --                                  ______________________________________                                    

Thus, it was observed that the intensity of the odor of smelling strip Cdecreased strongly in the first 24 h and could no longer be detected atthe end of 3 days.

Smelling strip B kept a strong odor at the end of 3 days, which howeverabated rapidly within the following week, whereas smelling strip A,whose odor intensity was at the begining inferior to that of smellingstrip B (and of a distinct odor character anyway), kept henceforth apractically stable intensity and still developed a perfectly perceptiblefragrance a month and a half after having been dipped in the compoundaccording to the invention. Furthermore, according to the perfumers, thequality of the odor of smelling strip A had suffered no deterioration atthe end of this period.

EXAMPLE 18

Test of stability against oxidation by gas phase chromatography (GC)

The qualitative evolution described in the preceding example, on thebasis of the perfumers' odor evaluation, was entirely confirmed, in aquantitative manner, by means of gas phase chromatography (GC)measurements.

The following method was applied.

Onto three standard smelling strips (7×147 mm) there was deposited adrop of respectively 3-(4-tert-butyl-2-methyl-1-phenyl)propanal(smelling strip A), 3-(4-tert-butyl-1-phenyl)propanal (smelling strip B)and of 3-(4-tert-butyl-1-phenyl)-2-methylpropanal (smelling strip C).

The soaked area off the smelling strips (˜20 mm) was cut and immersedfor 1 h in CH₂ Cl₂ (1 ml) contained in closed test tubes, withoccasional stirring.

Before injecting the solutions in a GC apparatus,bis-(trimethylsilyl)acetamide (Aldrich, 4 drops, ˜30 mg) was added toeach of the three solutions, to form the trimethylsilylic ester of theacid into which the aldehyde extracted from each of the smelling stripshad been converted by air oxidation. It had in fact been observed thatthe GC signal of said esters was distinctly less broad than that of thecorresponding acids, thus allowing a far more precise integration.

The three solutions were then injected into a GC apparatus at regulartime intervals, adapted to the oxidation speed observed for each of thethree above-mentioned aldehydes. The signals corresponding to thealdehyde and the trimethylsilyl ester (the latter being proportional tothe amount of formed acid) were integrated and the results obtainedrepresented on the graph of FIG. 1.

On this graph, the percentage of aldehyde and corresponding acid arerepresented as a function of time. The curves represented translate theaverage values obtained in two distinct experiments, carried out witheach of the compounds whose structures are represented.

It is clearly apparent from FIG. 1 that the compound according to theinvention, i.e. 3-(4-tert-butyl-2-methyl-1-phenyl)propanal, is far morestable against air oxidation than its known isomer,3-(4-tert-butyl-1-phenyl)-2-methylpropanal or LILIAL®, which, at the endof about 4 days, has been converted to the extent of 80% into thecorresponding acid, which is practically odorless.

When comparing the compound of the invention with its known lowerhomologue, i.e. the 3-(4-tert-butyl-1-phenyl)propanal or BOURGEONAL®(origin: Naarden Int., Holland), again it can be clearly seen that thelatter, although far more stable than LILIAL®, has been converted up to70% into the corresponding acid at the end of about 20 days, whereas thealdehyde according to the present invention is still ˜90% stable.

It should be noted that these results cannot be imputed to differencesin volatility and/or polarity of the compound of the invention relativeto its known isomer LILIAL®. We have in fact measured the retentiontimes of these two compounds in two types of gas/liquid chromatography(GLC) columns, as well as the R_(f) values by thin layer chromatography(TLC). The results presented hereinafter show that there are nosignificant differences in these values.

    ______________________________________                                                                   Compound                                                                      of the                                                                 Lilial.sup. ®                                                                    invention                                          ______________________________________                                        Retention time GLC                                                                        silica column 5.27     6.06                                       [min]       Carbowax column                                                                             11.20    13.46                                      TLC: R.sub.f on SiO.sub.2 (eluting agent: CH.sub.2 Cl.sub.2)                                        0.60     0.56                                           ______________________________________                                    

We claim:
 1. Compound of formula ##STR15## wherein symbol X represents a--CHO group or an acetal group of formula ##STR16## symbols R', takenseparately, represent each a C₁ to C₄, linear or branched, saturated orunsaturated, hydrocarbon radical or, taken together, represent a C₁ toC₄ alkylene radical, which may be substituted, and symbol R represents ahydrogen atom or a methyl radical. 2.3-(4-tert-Butyl-2-methyl-1-phenyl)propanal.
 3. Use of a compoundaccording to claim 1 or 2 as a perfuming ingredient.
 4. Perfumingcomposition or perfumed article containing as active ingredient acompound according to claim 1 or
 2. 5. Perfumed article according toclaim 4, in the form of a perfume or a cologne, a soap, a bath or showergel, a shampoo or an after-shampoo product, a cosmetic preparation, abody or air deodorant, a detergent or fabric softener, or a householdproduct.
 6. Compound of formula ##STR17## wherein symbol R represents ahydrogen atom or a methyl radical.